There are many circumstances where it is desirable to measure the weights of articles in transit from one location to another. In many cases, such articles are carried by a conveyor system between the two locations. At present, in order to measure the weight of one of the articles it is necessary to transfer that article to a weighing system. In one arrangement, this entails either stopping the conveyor system while the article is transferred to a stationary weighing system. In another arrangement pushers and auxiliary conveyors are used so that the article can be transferred to a weighing system without stopping the main conveyor system. The article whose weight is to be measured will then normally be returned to the main conveyor system or to a further conveyor system for transit to the other location. In these known types of weighing systems, a delay in the transfer of articles between the locations is unavoidable. Further, transfer mechanisms for transferring the article whose weight is to be measured from the main conveyor system to a weighing system must be provided. This has the consequence that it is often not practicable to measure the weight of each of a plurality of articles being transferred in succession, except in cases where the inherent delays can be tolerated.
The present invention was developed to overcome this problem specifically in relation to the measurement of parcel weights in Post Office sorting systems and to provide a weighing apparatus capable of measuring weights of a plurality of parcels being transferred in succession between two locations, without excessive delays. However, the present invention is applicable to measuring the weights of any articles, and is particularly suitable for rigid and semi-rigid articles.